Recently, interest in an electric product, which can be driven by using a rechargeable battery, has increased due to depletion of fossil energy, and environmental pollution due to use of fossil energy. Accordingly, in view of technical development and demands for a mobile device, an electric vehicle (EV), a hybrid vehicle (HV), an energy storage system (ESS), and an uninterruptible power supply (UPS) have increased, demands for a rechargeable battery as an energy source have been rapidly increased.
The rechargeable battery attracts attention as a new energy source that is environmentally-friendly and with improved energy efficiency in that it is possible to innovatively decrease use of fossil energy, which is the primary advantage, while not generating a by-product when using energy.
Particularly, a rechargeable battery used in an EV, an HV, an ESS, and a UPS is configured by connecting a plurality of battery racks including a plurality of battery modules in order to charge or discharge high-output and large capacitance power. A relay control technique for controlling a current flowing in the battery rack by installing a relay is provided in the battery rack, in which high-output and large capacitance power is frequently charged or discharged, in order to protect the battery rack from overcharging, overdischarging, and a surge current.
However, when the relay installed by an installer for protecting the battery rack is abnormally installed to configure a closed circuit, in which only the relay and the battery rack are connected, without an external load, a short-circuit phenomenon occurs in the battery rack. When the short-circuit phenomenon occurs in some battery racks among the plurality of battery racks connected to secure high capacitance, a charging speed of each battery rack varies due to capacitance imbalance between the battery racks, and thus the first charged battery rack is overcharged, so that there is a problem in that the battery rack is damaged due to overheating or swelling, and as a result, the BPU and the electronic component connected with the battery rack are damaged.
In this respect, the present inventors completed an apparatus, a system, and a method of preventing a battery rack from being damaged by measuring a current, which, when a battery module is abnormally connected with a relay in some battery racks in installing the relay, which conducts or blocks a current flowing in the battery rack including a plurality of battery modules, so that a current exceeding a predetermined current limit value flows in the battery rack, prevent a short-circuit phenomenon that occurs in the battery rack in which the relay is abnormally installed, by controlling an operation state of the relay before the battery rack and the relay form a short circuit, and prevent capacitance imbalance between the battery racks by controlling an operation state of the relay when a voltage difference between a plurality of battery racks exceeds a predetermined voltage difference, thereby preventing the battery rack, a BPU, and an electronic component from being damaged.